In this study the exposure of mining vehicle operators, on an opencast goldmine
in Tanzania, to certain hazards specific to their occupation was assessed. The
aim was to quantify these levels of exposure in order to estimate the risk of
health effects but also to report levels of these hazards that exist on mining
vehicles. Three different hazards with different physiological effects were
assessed and it included exposure to whole-body vibration, A-weighted noise
and low frequency noise. In each case correctly calibrated instrumentation was
used and internationally accepted methods were followed. It was found that
mining vehicles commonly exposed operators to levels of whole-body vibration
within and above the ISO Health Guidance Caution Zone (HGCZ) and above the
ropean action level, which indicates the need for intervention and control.
These levels are a cause for concern and will likely lead to health effects. Noise
that damages human hearing (A-weighted noise) was present in high levels on
mining vehicles, in each case being higher than the permissible exposure limit of
85 dB(A). Thus operators of mining vehicles are exposed to noise levels that will
damage their hearing in time. A potential hazard in the occupational world, low
frequency noise, was also included in the assessment. Literature indicates that
low frequency noise is capable of causing many human health effects and thus
levels on mining vehicles were reported in order to give an indication of what
levels may be expected in this department of mining. It was found that much of
the sound energy measured on vehicles was located in the low frequency range.
In the lowest frequency band measured, Leq levels of more than 100 dB(Z) were
commonly found. Controls should be implemented as far as is reasonably
practicable to ensure that operators are not exposed above recommended or
permissible levels for each hazard. These controls can include good
maintenance of vehicles and roads to reduce whole-body vibration, sound
proofing of vehicle cabs along with hearing protection devices to protect hearing
and further research regarding the exposure and health effects caused by low
frequency noise. Following literature indicating the physiological effects of low frequency noise exposure and also the presence thereof in different occupations, it is concluded that A-weighted noise measurements alone can not be used when
quantifying the risk involved in a given acoustical environment. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2009
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:nwu/oai:dspace.nwu.ac.za:10394/6415 |
| Date | January 2009 |
| Creators | Schmidt, Brian Ronald |
| Publisher | North-West University |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
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